
® U.S. Registered Trademark
Copyright © 2000 Honeywell Inc. • All Rights Reserved
SCHEMATIC
MM-3 MASTERTROL®
MINI-ZONE™-3
69-1362
TheMastertrol® Mini-Zone™ -3 Zone Control Panel,
Model MM-3, controls up to 3 zones on any single
stageheatingand cooling system.Eachzoneiscon-
trolled by a thermostat which operates a motorized
damper in the it’s zone duct to control the flow of
conditioned air to the zone. (Up to 2 dampers may
be wired to a single zone.When 3 or more dampers
are required a Slave Damper Control Relay, Model
SDCR, is required.)
The Zone 1 Thermostat requires a manual
changeover subbase with“O”and“B” terminals.The
“O” terminal must make with R when the subbase is
switched to the COOL Mode.The “B” terminal must
make with R when the subbase is switched to the
HEAT Mode.When the Zone 1 Subbase in either the
Heat or Cool Mode, any one of the 3 zone thermo-
statscancallforthe respective mode.Thezonether-
mostat will energize it’s zone relay which activates
the heating or cooling controls, opens it’s zone
damper and close the dampers to the zones that are
satisfied.When all zonethermostats are satisfied the
heating or cooling will shut off and all zone dampers
will return to their normal position.The normal posi-
tion of the zone dampers is set by the OPEN/
CLOSED slide switch next to the motor terminals.
SYSTEM CONNEC-
TIONS: The MM-3 Sys-
tem Terminals on the far
left side of the panel are
usedtowiretotheHVAC
Unit.Theseterminals are
isolated “dry” switching
contacts similar to any
typicalthermostat.These
terminals are wired tothe
HVACUnitTerminals the
same as any thermostat
would when not using
this zone control panel.
The MM-3 connections
used are typically the R-
G-Y-W terminals wired
the the HVAC Unit Con-
trol Center.
HYDRO-AIR Systems - When using the MM-3 with
a Hydro-Air System, one which uses a hot water coil
in the air handler to provide heating in place of a
furnace, the wiring is almost similar to that shown.In
thisapplicationtheHeatRelayshown maybeazone
valve or circulator relay. The Fan must often be
brought on with the call for Heat.To provide for this,
jumper the Gh and G terminals on the MM-3.
OIL FURNACES -When using the MM-3 with an Oil
Fired Furnace to provide heating the T and T termi-
nals on the Oil Burner Primary Control must wire to
theB andW wires.
NOTE:Once operational if the Oil
Furnace continues to run when all zones are satis-
fied, reverse the B andW wires on the MM-3.
IMPORTANT:Whenusingthe MM-3 as onlya2Zone
Panel, the Zone 3 Relay must remain plugged into
it’s socket.
ZONE THERMOSTAT WIRING - The MM-3 can be
used with several different single stage thermostats.
The wiring shown is for the following recommended
thermostats:
Zone 1 Thermostat Zone 2 and 3Thermostat
TRT(-W) and MCRS(-W) TRT(-W)/T87F
/T87F and Q539A
T8090T1003* T8090T1011*
T8602C T8602D
T8601C* T8603D*
*These thermostats may require additional wires.
Refertothewiringinformation included with the ther-
mostat for complete information.
DAMPER MOTOR WIRING - This diagram shows
Trol-A-Temp’s typical power open-power closed op-
posed blade damper motors. Note the jumper wire
required on the motor terminals 2 and 5. Round
Spring Return Dampers can also be wired to the
MM-3.When using the ARD-PC (D835), wire to the
M1 and M6 terminals. When using the ARD-PO
(D837), wire to the M1 and M4 terminals.
456Z
123X
ZONE 2 DAMPER MOTOR
M1
456Z
123X
COMPRESSOR RELAY
IN OUTDOOR
CONDENSING UNIT
M6
M4
M1
T6/Y
T5/R
T4/W
T6/Y
T5/R
T4/W
R
O1
G1
B1
2
1
5/R
6/Y
4/W
Y
R
24 VOLT 40 VA
TRANSFOMER
MODEL PMT-40
HEAT RELAY
ZONE 2 THERMOSTAT
ZONE 1 THERMOSTAT
AND SUBBASE
O
B
G
Gh
Y
W
Y
R
W
O
G
B
C
W
ZONE 1 DAMPER MOTOR
24 VOLT
TRANSFORMER
FAN RELAY
SYSTEM
ZONE 3
ZONE 2
C
O
C
O
R
C
M6
M4
T6/Y
T5/R
T4/W
DAMPER
ZONE 1
C
O
5/R
6/Y
4/W
ZONE 3 THERMOSTAT
MODEL ARD-PC (POWER CLOSED)
ZONE 3 DAMPER MOTOR
M6
M4
M1
THERMOSTAT
MASTERTROL®
MINI-ZONE™-3
CONTROL PANEL
CHANGEOVER
CONTROL
M13558
G
HVAC UNIT CONNECTIONS